1. Field of the Invention
The invention relates to vehicle warning light systems and, more particularly, to a warning light system employing a high-intensity flash lamp.
2. Description of the Prior Art
Prior art vehicle warning light systems commonly comprise a taillight assembly, a headlight assembly, a turn signal assembly, and an emergency flasher assembly, all employing incandescent light bulbs. Each of these assemblies operates in a well-known manner to illuminate the roadway, to indicate an impending stop or slow-down, to indicate an impending turn, or to indicate an emergency condition of some nature.
The conventional vehicle warning light system suffers from certain drawbacks under modern driving conditions. For example, the Interstate network of highways is sufficiently complete that it is possible in many cases to drive at relatively high speed for an extended period of time. Particularly near large cities, traffic congestion occurs and it is very common for a large number of cars to travel at high speed without adequate spacing between cars. Accordingly, if a given vehicle should be required to stop suddenly or slow-down rapidly, the following vehicle too frequently impacts the vehicle preceding because the following driver was not warned adequately of the impending stop or slow-down and, hence, could not initiate a braking operation or other evasive maneuver quickly enough. A similar result often happens when a given vehicle makes a turn, because the turning vehicle's turn signal lights may not adequately warn the following driver of the maneuver about to be executed. In short, conventional warning light systems employing incandescent light bulbs often fail to achieve their desired ends.
The problem primarily is one of sufficiently stimulating the following driver so that he immediately is aware that the preceding vehicle is about to stop, slow-down, or turn. Accordingly, if the following driver is alerted to the situation at hand, appropriate action may be taken to avoid a collision.
Prior art approaches to the problem have had certain drawbacks. For example, U.S. Pat. No. 3,258,746 discloses an automotive anti-collision beacon employing a high-voltage, gas-filled, electronic discharge lamp used in combination with a conventional stoplight so that the high-voltage lamp will be discharged only under certain conditions of vehicle deceleration. Alternatively, a plurality of G-sensitive switches set at different deceleration levels may be employed to flash separate high-intensity lamps progressively as a function of the rate of deceleration. The deficiencies of this type of system arise from the very nature of the switch employed to discharge the lamps. For example, riding on a rough road quite easily could flash the high-intensity lamp, thus giving a false indication of an impending stop. Conversely, if a stop is not made sufficiently rapidly, the lamp never will flash, thus failing to provide a warning to a following driver. These problems are exacerbated by driving uphill, downhill, or around curves.
Another approach to the problem is shown by U.S. Pat. No. 2,751,575, wherein an emergency incandescent light is disposed at the rear of the vehicle and is employed in conjunction with the conventional stoplight system. Depending upon whether the headlights are illuminated, the emergency light is illuminated either by a G-sensitive mercury switch or by extremely heavy brake pedal pressure. In one embodiment, the emergency light remains illuminated until the brake pedal pressure is released. One of the chief drawbacks of this system is that the emergency light is not illuminated until a panic-stop condition is approached. Accordingly, it very well may be too late to warn a following driver and this system would fail to achieve its goals. Moreover, once the emergency light is illuminated, it remains illuminated until the brake pedal pressure is released. Because a conventional incandescent lamp is employed, it is quite possible that a following driver's attention will not be captured in any event because (1) the intensity of the lamp is relatively low, and (2) the constant illumination of the emergency lamp provides little stimulus to a following driver.
Other examples of vehicle warning systems could be given. In each case, however, the system fails to provide an adequate warning to the following driver at the initiation of a vehicle operation so that the following driver can take appropriate evasive action.